SHORT COMMUNICATIONS 283

Wilson Bull., 99(2), 1987, pp. 283-284

Notes on the Mountain Caracara (Phalwboenw megdopterns)in the Argentine puna.- The Mountain Caracara (Phalcoboenus megalopterus) is a conspicuousspecies in the Ar- gentine puna zone. While not as abundant over largeareas of the puna as are other caracaras (Polyborus and Milvugo), in other habitats of Argentina, we found four pairs along the 70 km of road from Cuesta de Auzul Pampa to Abra Pampa, Jujuy Province (3500 m elev.). As is the case with Polyborus, P. megalopterus were concentrated near towns where they fed on carrion and refuse. Eighteen individuals were seen from one spot on the outskirtsof Abra Pampa as they sat on power poles or fence posts. Three were collected as part of a largerstudy; 2 at Abra Pampa and I at Cuestade Auzul Pampa. Although they were obtained randomly, all 3 had entire legs or portions of feet missing. Their wounds were healed and appeared to be old. The form of injury was identical to what we have previously seen in raptors that were victims ofjaw traps. One adult was missing the right leg about 2 cm below the junction of tibiotarsus and tarsometatarsus,another adult was missing the hallux, and the subaduhwas missing the entire left foot. Still another adult seenappeared to be lacking an entire foot. Fmncois Vuilleumier (pet-s.comm.) has examined 34 specimensof Phafco- boenus during the courseof his continued interest in caracarasand has noted 3 Phalcoboenus with missing toes or feet: One from Chile near the Argentina boundary was missingthe foot and had a well-healed leg similar to our finding. Other genera of caracarasfrom different habitats have not shown a similar incidence of foot injury. We traveled 6586 km of roads in Northern Argentina and observed more than 400 Milvago chimango. 10 M. chimachima, and 2 14 Polyborus plancus, and none had conspicuousleg or foot injuries. None of 3 M. chimango. 2 M. chimachima. and 4 P. plancus collected had similar injuries. Caracarasare unique among Fahonidae for building their own stick nests. Brown and

FIG. 1. Left side of the figure shows the cement poles with the nest near the top of the pole. Right side of figure shows a young caracarain the nest. 284 THE WILSON BULLETIN l Vol. 99, No. 2, June 1987

Amadon (1968) found no instance of caracaras using man-made objects as nest supports, although at least 3 of the 4 species of Phalcoboenus do use cliffs in addition to trees and the ground. Five nests of P. megu1opteru.sreported by Wolfe (195 1) from Chile all were on cliffs with very little nest material (only a few sticks and bits of rubbish). Similarly, Johnson (1965: 265) indicated that all megulopterus nests are on cliffs with only “a little dry dung to serve as an apology for a nest.” Housse (1938) did not, in fact, find nests, but thought they must nest in trees as some birds ranged down out of the cordilleras into forested country. All of the more than 30 nests of P. carunculatus (considered a race of megaloptencs by Vuilleumier [ 19701 and Stresemann and Amadon [ 19791) studied by DeVries et al. ( 1983) in Ecuador were on cliffs and seemed to be better constructed than those described above. We could not find references indicating their use of man-made objects for nest placement, but we do not doubt they use them. In the 28 km between Tres Cruces (4200 m elev.) and Abra Pampa, where the road follows a cement high tension power line, we found 2 nests 10 km apart on the cross arms of powerline poles. The nests were considerably more than a few sticks, bits of dung, and rubbish (both nests were similar in size and construction) (Fig. 1). Sheep or llama wool was also incorporated into the nests. Both nests were substantial, and we suggest that they had been used repeatedly with material added annually. This should, however, also be the case with nests elsewhere on cliffs, and we are unable to explain the differences. The only other species in the puna that could build a nest of similar size are the Red-backed Hawk (Buteo polyosoma) and the Puna Hawk (Buteo poecilochrous), but their nests are very different in structure from those we found. Acknowledgments.-Funds to work in Argentina in 1984 were provided for by a Brigham Young University professional development grant. The specimens are on deposit in the Bean Museum, Brigham Young University, and Museo Argentino de Ciencias Naturales, Buenos Aires. We thank W. G. and B. Vasina and R. Straneck for their aid in Argentina, and F. Vuilleumier for lengthy discussions.

LITERATURE CITED

BROWN, L. AND D. AMADON. 1968. Eagles, hawks and falcons ofthe world. Vol. 2. McGraw- Hill, New York, New York. DEVRIES, T., J. BLACK, D. DESOLIS, AND C. HERNANDEZ. 1983. Historia natural de1 Cu- riquingue (Phalcoboenus carunculatus) en 10s paramos de1 Antisana y Cotopaxi de1 Ecuador. Ediciones de la Universidad Catolica, Quito, Ecuador. HOUSSE,P. R. 1938. El tiuque cordillerano (Phalcoboenus megalopterus) (Meyen). Revista Chilean de Historia Natural 4 1: 13 l-l 34. JOHNSON,A. W. 1965. The birds of Chile and adjacent regions of Argentina, Bolivia, and Peru. Vol. 1. Platt Establecimientos Graficos S., Buenos Aires, Argentina. STRESEMANN,E. AND D. AMADON. 1979. Order Falconifonnes. Pp. 27 l-425 in Check-list of birds of the world (E. Mayr and G. W. Cottrell, eds.). Mus. Comp. Zool., Cambridge, Massachusetts. VUILLEUMIER, F. 1970. Generic relations and speciation patterns in the caracaras (Aves: Falconidae). Breviora No. 355: l-29. WOLFE, L. R. 1951. Eggs of the falconiformes. Pt. 3. Oologists ’ Record 25:49-54.

CLAYTON M. WHITE AND DOUGLAS A. BOYCE, Dept. Zoology, Brigham Young Univ., Provo, Utah 84602. Received 14 July 1986, accepted 2 Dec. 1986.